When I was on my mission, my companion received a letter one night from his mom with news that should have rocked the Mormon world.

If it hadn't been a total myth.

She said that a young man in her stake had received his mission call recently and when he opened the envelope, he found a single sheet of paper containing a phone number. He dialed the number and anxiously waited as friends and family looked on.

Finally the voice of an operator came on the line and said, "Please hold for President Hinckley."

Next, the astonished young man heard the prophet's voice.

"Elder," he said. "We're opening mainland China for missionary work, and you're going to be one of the first missionaries to begin proselyting. Are you up for the task?"

Now, needless to say, I was more than a little skeptical of this story when he first read it to me. Wouldn't we have heard from the member of our local ward if China had really been opened to missionaries? Wouldn't the church have made some sort of an announcement?

But my companion took it all on faith. After all, his mom had heard it from someone in her stake! Can sources get more reliable than that?

News spread fast through the mission. District meetings and P-day lunches were dominated by talk of the new mainland China mission. Elders wondered aloud whether the Mandarin-speaking missionaries in our mission would be reassigned.

"They probably need all the help they can get," the excited elders would say. "After all, there can't be very many missionaries in the world who speak Chinese!"

Without regular Internet access, none of us had a way to verify the claim in the letter, and so many of us turned to the members in our wards and branches. And while none of them had heard of such an announcement, many of them figured that if the missionaries knew about it, it must be true.

"It just goes to show what kind of miracles the Lord can accomplish," the members would say, beaming.

Well, eventually the elders who had written enthusiastic letters home requesting more information received word that the rumors were false.

In the end, I don't think much harm was done. No testimonies were too badly shaken, and besides enduring a few minutes of disappointment, the work went on.

I guess I shouldn't have been surprised when a couple days ago my co-workers and I were swapping some of our favorite Mormon myths and that exact same story surfaced. Apparently, my mission was not the only one that had fallen prey to this particular rumor.

A new Web site pitching itself as a Mormon myth-buster recently launched, causing me once again to wonder about why we Latter-day Saints take so much joy in spreading unsubstantiated stories about ourselves.

The site, HolyFetch.com, is run by Casey Cummings, a resident of Kaysville, Utah, who says he got interested in the world of Mormon myths when he was on his mission in Austria.

The site's basic format is similar to that of sites like snopes.com. People submit popular Mormon myths, and then Cummings investigates them and deems them either "true" or "false."

I'm frankly surprised that something like this hasn't been created by now. Or maybe it has been, and it just isn't very well publicized. In any case, the fact that such a Web site exists (and is enjoying moderate success by most accounts) is a comment, I think, on LDS culture.

There are, of course, different categories for these Mormon myths.

For example, many of the stories seem to revolve around Mormon miracles that are designed to wow non-members. (Ever heard the one about the zone conference scheduled in the Twin Towers on Sept. 11, 2001, that was canceled by divine inspiration? Yeah, turns out it's not true.)

As a historically persecuted faction that is now globalizing -- and grabbing more frequent headlines in the process -- our members, perhaps feeling vulnerable, seem exceptionally prone to spreading faith-promoting rumors that may or may not be true.

Then there are the stories we love to tell in talks and Sunday School lessons. (There is no documentation of a prophet, for instance, who has ever said that today's youth were all generals in the War in Heaven.) These stories are probably told with good intent -- to inspire righteousness and faith in our fellow Saints -- but many of them are not true.

And, of course, we have the high priest group theories designed for no apparent purpose other than to stimulate "deep" doctrinal discussions. Perhaps the most oft-quoted theory in this category is that of Cain being the real Bigfoot. There is, of course, no real way to prove or disprove this type of thing, but they seem very popular among many local church scholars.

Like I said at the beginning of this article, there is probably no real harm done by such stories -- at least not usually. But I worry about the few among us who base their testimonies on such rumors. When they find out that the stories aren't true, I hope they still know the church is.